I think this is to tough. ACB and Euroleague is not as far as you might think from NBA....specially from certain teams.
This is a common belief outside of the USA. I expect it is about as accurate as saying US Futbol is not as far from Top Euroleague as you might think.
We can just give opinions, make forecasts...but I think people might respect a decision, an important one with 19 yo + looser franchise (europeans hate playing with looser teams)
Nobody like to play for a loser, even in the USA! hehe
Especially in Basketball, where there are only 12 players per team, a team's ability to win is based on its parts. So if you are a great player, you should believe that the team will stop losing so much with your arrival.